This is a software transactional memory (STM) system developed at Wyatt Technology for use in their Dynamics data collection and analysis package. This package includes the STM library itself (including some data structures built on top of the core STM functionality) and a suite of test programs to ensure its correct functioning.
The home for this project is on github. There is also a google group for discussing usage and developement.
The main STM library is in the wstm (headers) and src (implementation) directories.
In the testing directory there are some programs that exercise the library:
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unit-tests: Unit tests for the STM library. This program uses the boost test library, for more information on command line arguments see that library's documentation.
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correctness: Random stress test for the STM library. Makes random updates to a set of transactional variables in multiple threads pausing periodically to check that the library is behaving properly under load. This is meant to be run for long periods of time.
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contention: Test how much contention is inherent in the STM system. This is done by running some number of threads with each thread updating its own private set of variables. The number of transactions that each thread can commit over some time period is tracked and reported. Since each thread is accessing variables that are not accessed by any other thread we won't have any contending transactions, all we're measuring is how much contention is inherent in the STM implementation itself.
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channel: This is a stress test for the multi-cast channel data structure that is part of the library.
We've been using this library at Wyatt Technology in an application that we ship to customers for years now. As such it can be considered stable. While it is stable, it does have some contention issues if run with too many threads. How many threads is too many depends on how intensly the library is being used (at Wyatt we have no problems with up to 8 computation heavy threads plus a few more IO bound threads, all of which are making medium to heavy usage of transactions). If you are going to use the library in a non-experimental manner then it would be best to do some prototyping first to see if you get performance that is good enough for your application. At some point we plan to remove this contention, but it hasn't been enough of an issue for us at Wyatt yet for much time to be devoted to it.
The documentation for using the library is contained in the doc sub-directory.
This library has been tested on Windows using Visual Studio 2015, Linux using GCC 4.9 and Clang 3.4, and OSX using Apple Clang 7.0. Earlier versions of these compilers probably won't work. It also requires the boost library, version 1.57 or newer. For more details on building the library and associated test programs see BUILDING.md.
See the BUILDING.md file for more information on building the library and associated test programs.
This library and its associated test programs are licensed under a BSD license, see LICENSE for more information.